JP3025423U - A hand truck that can easily move up and down steps - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To easily and safely control a trolley by a pusher alone at a step on a road surface that impedes traveling in the process of placing a load on a trolley and moving the trolley, and to pass the trolley quickly. To obtain a hand cart that can be easily moved up and down. SOLUTION: A movable plate 1 which is movable with respect to the carrier 2 below a carrier 2 of the cart, and a pair of rotatable front large-diameter drive wheels 4a attached to the front part of the lower surface of the movable plate 1. And a pair of fixed rear large-diameter main driving wheels 4b attached to the rear portion, and a pair of front small-diameter auxiliary wheels 6a and rear small-diameter auxiliary wheels 6b attached to the front end and the rear end of the lower surface of the loading platform 2, respectively. A traverse mechanism for moving and fixing the movable plate 1 in the front-rear direction with respect to the loading platform 2 and a handle 8 attached to the loading platform 2.

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

 The present invention is applied to a trolley that is mainly used in the field of logistics, and in the process of loading and moving luggage, it is a flat road such as a step between the top of the curb of the sidewalk and the road surface of the car, which is an obstacle to running. The present invention relates to a hand truck that can be easily lifted up and down so that it can be easily and safely passed by a hand pusher alone.

[0002]

[Prior art]

 Conventionally, the trolleys that have been generally used are premised on the use on a flat road, and none have been developed in consideration of the elevation of steps. Therefore, when using it, when there is an obstacle such as a step in the process of moving the trolley after placing the luggage on the trolley of the trolley, it is necessary to bypass or to assist a third party. Not only does it require a great deal of labor for the pusher, but it also poses a risk to the transfer work, such as a collapse of the load or injury to the worker. In particular, the heavier the load, the more pronounced it becomes, and the work requires more effort and caution.

[0003]

[Problems to be solved by the device]

 In view of the above, the present invention allows a pusher to easily and safely control a truck at a step such as a curb on a road surface that impedes traveling during the movement of a luggage on a truck, and allows the truck to be handled quickly. The purpose of the present invention is to obtain a hand-pushed trolley that has a function that enables it to easily move up and down steps.

[0004]

[Means for Solving the Problems]

 The present invention has been made in view of the above viewpoints, and the basic configuration thereof is generated by controlling the wheel positions of the carriage with respect to the center of gravity of the cargo bed when the cargo is placed on the carriage. It utilizes the change in moment with one of the front and rear wheels as the fulcrum.

Specifically, a movable plate that is movable with respect to the bed under the bed of the bogie, and a pair of rotatable front large-diameter drive wheels that are attached to the front portion of the lower surface of the movable plate. And a pair of fixed rear large-diameter drive wheels attached to the rear and a pair of front small-diameter auxiliary wheels and rear small-diameter auxiliary wheels attached to the front and rear ends of the lower surface of the cargo bed, respectively. An object of the present invention is to provide a hand truck that includes a traverse mechanism that moves and fixes a movable plate in the front-rear direction with respect to the loading platform, and a handle attached to the loading platform to easily raise and lower a step.

[0006]

[Action and Example]

 The configuration of the first embodiment of the present invention will be described below with reference to FIGS. In this embodiment, a traverse mechanism which is also called a rack and pinion or ratchet system is adopted. On the lower surface of the movable plate 1, two front driving casters 3a and two rear driving casters 3b, which are opposed to each other at the front and the rear, are attached, and each of the driving casters 3a and 3b has a front driving of a required large diameter. A wheel 4a and a rear drive wheel 4b are attached. In this case, the front drive wheel 4a is rotatable and the rear drive wheel 4b is fixed.

Casters 5a and 5b for auxiliary wheels are attached to the front and rear ends of the lower surface of the loading platform 2 of the truck located above the movable plate 1, and the casters 5a and 5b are attached to the casters 5a and 5b, respectively. A front auxiliary wheel 6a and a rear auxiliary wheel 6b are attached to each of them. The relationship between the main driving wheels 4a and 4b and the auxiliary wheels 6a and 6b is such that the main driving wheel> the auxiliary wheel is satisfied, and the main driving wheel >> the auxiliary wheel is desirable.

Among the auxiliary wheels 6a and 6b, the front auxiliary wheel 6a is fixed and the rear auxiliary wheel 6b is rotatable.

As shown in FIGS. 4 and 5, on the upper surface of the movable plate 1, guides 7a as linear motion bearings are attached at positions corresponding to the respective wheel attachment positions. On the other hand, two parallel guide rails 7b extending in the front-rear direction are attached to the truck carrier 2. The guide 7a is fitted to the guide rail 7b so that it can slide along the guide rail 7b. Thereby, the movable plate 1 is configured to be movable in the front-rear direction with respect to the truck carrier 2.

Further, the handle 8 is not limited to a handle perpendicular to the truck carrier 2 and is provided with an angled handle so that a force can be easily applied when the truck is moved up and down.

As shown in FIG. 6 and FIG. 7, the handle 9 is rotatably attached to a rotatable attachment shaft A attached to the left and right sides on one side of the rear end of the truck carrier 2. Further, at a position near the mounting axis A of the handle 9, pawls 10a and 10b, which are respectively locked to the later-described pawl wheels 11a and 11b, are attached to the shaft rod C.

In addition to the handle 9, symmetric claw wheels 11a and 11b having locking directions opposite to each other and a bevel gear 12a are fixed to the mounting shaft A.

A changeover switch 17 is attached to one end of the shaft rod C. The pawls 10a, 10b are integrally fixed or loosened depending on the rotation direction of the switching switch 17, and when fixed, the pawls 10a, 10b are engaged with one of the corresponding pawl wheels 11a, 11b according to the rotation direction of the handle 9. It is configured.

In addition, the lower part of the truck carrier 2 is provided with a pawl 10a and a pawl wheel 11a as stoppers for preventing reverse rotation of the mounting shaft A when the rotation direction of the mounting shaft A is determined above. A claw 10c for moving and a claw 10d corresponding to the claw 10b and the claw wheel 11b are attached. The pawl 10c and the pawl 10d can be switched between fixed and loose by a changeover switch 18, like the pawls 10a and 10b.

The center of rotation of the bevel gear 12b meshing with the bevel gear 12a is fixed to a worm shaft 13 rotatably supported by a bearing 20 fixedly mounted on the lower surface of the carriage carrier 2. As a result, the worm shaft 13 rotates in the same direction as the rotation of the bevel gear 12b determined by the rotation direction of the handle 9.

As shown in FIGS. 8 to 10, the worm shaft 13 meshes with a rotatable worm gear 14 pivotally mounted on a shaft B provided on the lower side of the central portion of the truck carrier 2. ing. A pinion gear 15 is fixed to the shaft B in addition to the worm gear 14. The pinion gear 15 is meshed with a rack 16 extending in the front-rear direction on one side surface of the movable plate 1.

In the above configuration, the changeover switches 17 and 18 are set so that the claw 10a, the claw 10c, and the ratchet wheel 11a mesh with each other as shown in FIG. Then, when a force is applied to the handle 9 in a constant circumferential direction about the mounting axis A, the handle 9 including the claw 10a and the ratchet wheel 11a rotate integrally only in the clockwise direction. At this time, the claw 10c is in a state of sliding with respect to the ratchet wheel 11a.

When a force is applied in the circumferential direction opposite to the above, the claw 10a and the ratchet wheel 11a slide, and only the handle 9 including the claw 10a rotates with respect to the mounting axis A. Further, since the claw 10c and the ratchet wheel 11a mesh with each other, the mounting shaft A does not rotate in the reverse direction.

When the ratchet wheel 10a obtains a torque, the bevel gear 12a is fixed to the mounting shaft A, so that the torque is transmitted to the bevel gear 12a. The torque, which is changed in direction by 90 degrees by the bevel gears 12a and 12b, causes the worm shaft 13 to rotate in the circumferential direction. By thus rotating the worm shaft 13 in the circumferential direction, a thrust is generated in the longitudinal direction of the worm shaft 13, and the worm gear 14 is rotated about the axis B. Since the worm gear 14 and the pinion gear 15 are fixed to the shaft B, the pinion gear 15 also rotates. The torque obtained by the pinion gear 15 becomes the thrust exerted on the rack 16. Therefore, the movable plate 1 moves in any one of the front and rear directions.

Further, if the changeover switches 17 and 18 are rotated so that the claw 10b, the claw 10d, and the ratchet wheel 11b are meshed with each other, the mounting shaft A rotates in the opposite direction to the above, and torque in the opposite direction is generated. Since it is generated, the movable plate 1 moves in the opposite direction to the above.

Next, the configuration of the second embodiment of the present invention will be described with reference to FIGS. 11 to 17. In this embodiment, a traverse mechanism which is also called a ball screw or rotary handle system is adopted. As shown in FIGS. 14 and 15, the method of attaching the guide 7a as a linear motion bearing in the movable plate 1 and the guide rail 7b in the truck carrier 2 is in accordance with the rack and pinion and ratchet method described above.

The handle 9 is fixed to the timing belt wheel 22. The timing belt wheel 22 is rotatably attached to a shaft 27 attached to the handle 8.

As shown in FIG. 17, a timing belt wheel 21, a ratchet wheel 11a, a ratchet wheel 11b, and a bevel gear 12a are fixed to the mounting shaft A. Here, similarly to the rack-and-pinion and ratchet system described above, the ratchet wheels 11a and 11b are attached in a symmetrical direction, and similarly, on the cart carrier 2, the claws 10c and 10d corresponding to the ratchet wheels 11a and 11b are similarly mounted. Further, a changeover switch 26 for switching between the claws 10c and 10d is provided. By rotating the changeover switch 26, either one of the claws and the corresponding ratchet wheel mesh with each other. In this case, as shown in FIG. 17, the pawl and the ratchet wheel function as stoppers for keeping the rotation direction of the mounting shaft A constant.

The timing belt wheel 21 and the timing belt wheel 22 are laid flat by a timing belt 23, as shown in FIG. Then, as shown in FIG. 16, the bevel gear 12b meshing with the bevel gear 12a is fixed to the screw shaft 25.

The screw shaft 25 is rotatably supported by a bearing 20 fixedly provided on the lower surface of the carriage carrier 2. As shown in FIG. 12, the screw shaft 25 is engaged with a ball screw 24 fixed to the side surface of the movable plate 1, and the screw shaft 25 rotates in a constant circumferential direction so that the ball screw 24 is screwed. 25 Move in the longitudinal direction.

In the above configuration, as shown in FIG. 17, the changeover switch 26 is used to set the claw 10c and the claw wheel 11a so as to mesh with each other. In this case, the handle 9 and the mounting shaft A can rotate only clockwise. When the handle 9 is rotated clockwise, the timing belt wheel 22 is rotated, and the torque is transmitted to the timing belt wheel 21 via the timing belt 23, and the mounting shaft A is rotated clockwise.

Since the torque of the mounting shaft A is transmitted to the bevel gear 12b and the screw shaft 25 rotates clockwise, as described above, the ball screw 24 moves in the longitudinal direction of the screw shaft 25 to move the movable plate. 1 slides.

Contrary to the above, if the changeover switch 26 is rotated and the pawl 10d and the ratchet wheel 11b are set again so that they mesh with each other, the handle 9 and the mounting shaft A can rotate only counterclockwise. The movable plate 1 slides in the opposite direction to the above.

Now, the operation will be sequentially described based on the rack-and-pinion and ratchet system of the first embodiment and based on the operation explanatory diagrams shown in FIGS. 18 to 29. In this case, FIGS. 18 to 23 show a case of going up a step, and FIGS. 24 to 29 show a case of going down a step.

First, the case of going up a step will be described. When the high step A approaches from the low road surface (Fig. 18), the changeover switches 17 and 18 are set to the forward movement side, and the steering wheel 9 is applied with a force in the circumferential direction about the mounting axis A to move the traverse mechanism. To move the movable plate 1 to the front. At this time, the movable plate 1 is positioned so that the rear drive wheels 4b are near the center of gravity of the luggage carrier including the luggage (FIG. 19).

Therefore, the rear driving wheel 4b is used as a fulcrum, the handle 8 is pushed downward, the rear end auxiliary wheel 6b is grounded on the ground, and the carriage is moved in the horizontal direction of the ground to move the front driving wheel 4a to the upper edge of the step A. (Fig. 20). Next, the changeover switches 17 and 18 are set in the opposite manner to the above, the handle 9 is moved while applying a force in the traveling direction of the truck, and the traverse mechanism is used again to move the truck carrier 2 forward (Fig. 21). At this time, the movable platen 1 is positioned so that the front drive wheel 4a is near the center of gravity of the bed including the luggage.

At this time, contrary to the above, the front drive wheel 4a is used as a fulcrum, the handle 8 is pulled upward, and the tip auxiliary wheel 6a is grounded to the step A (FIG. 22). When the rear drive wheel 4b goes over the step A, the changeover switches 17 and 18 are again set to the forward direction and the handle 9 is moved, and the traverse mechanism is used again to move the movable plate 1 to the initial position. By returning to the step, the step elevation of the dolly can be completed (FIG. 23).

Next, a case of going down a step will be described. When going down, it is basically the reverse of going up, and the work is done with the handle 8 in the forward direction. First, when the trolley approaches the boundary between the step A and the ground (Fig. 24), the changeover switches 17 and 18 are set to the rearward direction and the handle 9 is moved to operate the traverse mechanism to move the movable plate. 1 is brought closer to the direction of the handle 8 and the rear auxiliary wheel 6b (FIG. 25). Similarly to the above, at this time, the movable plate 1 is positioned so that the front drive wheels 4a are near the center of gravity of the luggage carrier including the luggage.

Next, when the bogie is moved so that the respective driving wheels come into contact with the step portion A and the rear driving wheel 4 b exceeds the step portion A, the front driving wheel 4 a is used as a fulcrum and the handle 8 A vertical downward force is applied to the rear driving wheel 4b to contact the ground (Fig. 26).

After grounding, the changeover switches 17 and 18 are set in the opposite direction, the handle 9 is moved again, and the traverse mechanism is operated to move the cart carrier 2 in the traveling direction. At this time, the movable platen 1 is moved so that the rear drive wheels 4b are near the center of gravity of the bed including the load, and the rear end auxiliary wheels 6b are grounded (FIG. 27).

When the trolley is moved in the state of FIG. 27 (FIG. 28) and the front drive wheel 4a exceeds the step A, the changeover switches 17 and 18 are reversely set to the rear side again, and the traverse is performed. By operating the mechanism and returning the bogie to the initial state, the bogie step down can be completed (FIG. 29).

[0037]

[Effect of device]

 As is clear from the above description, according to the present invention, one of the front wheel and the rear wheel, which is generated by controlling the wheel position of the carriage with respect to the center of gravity of the cargo bed with the luggage placed on the carriage, is a fulcrum. Based on the principle of the lever utilizing the change of the moment, the pusher can easily and safely control the trolley to pass easily at the step of the road surface during the movement of the trolley with luggage. .

Since the position of the center of gravity of the luggage on the luggage carrier can be movably set so that the carriage can be easily handled when crossing a step, the lifting operation of the carriage can be easily performed.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration of a first embodiment of the present invention.

FIG. 2 is a front view showing the configuration of the first embodiment of the present invention.

FIG. 3 is a bottom view showing the configuration of the first embodiment of the present invention.

FIG. 4 is a front view of a main part showing a slide-fitted state of the movable plate and the truck carrier of the first embodiment of the present invention.

FIG. 5 is a side view of an essential part showing a slide fitting state of the movable plate and the trolley carrier according to the first embodiment of the present invention.

FIG. 6 is a side view of essential parts showing an operation mechanism portion for slidingly moving the movable plate with respect to the carriage carrier in the first embodiment of the present invention.

FIG. 7 is a bottom view of essential parts showing an operation mechanism unit for slidingly moving the movable plate with respect to the carriage carrier in the first embodiment of the present invention.

FIG. 8 is a front view of essential parts showing mutual engaging portions for slidingly moving the movable plate with respect to the truck carrier in the first embodiment of the present invention.

FIG. 9 is a side view of essential parts showing mutual engaging portions for slidingly moving the movable plate with respect to the truck carrier in the first embodiment of the present invention.

FIG. 10 is a bottom view of essential parts showing mutual engaging portions for slidingly moving the movable plate with respect to the truck carrier in the first embodiment of the present invention.

FIG. 11 is a side view showing the configuration of the second embodiment of the present invention.

FIG. 12 is a front view showing a configuration of a second embodiment of the present invention.

FIG. 13 is a bottom view showing the configuration of the second embodiment of the present invention.

FIG. 14 is a front view of essential parts showing a slidingly fitted state of a movable plate and a trolley carrier according to a second embodiment of the present invention.

FIG. 15 is a side view of essential parts showing a slide-fitted state of the movable plate and the trolley carrier according to the second embodiment of the present invention.

FIG. 16 is a bottom view of an essential part showing an operation mechanism part for slidingly moving the movable plate with respect to the carriage carrier in the second embodiment of the present invention.

FIG. 17 is a side view of essential parts showing an operation mechanism part for slidingly moving the movable plate with respect to the carriage carrier in the second embodiment of the present invention.

FIG. 18 is a state diagram showing a state in which the carriage approaches a step from a low road surface.

FIG. 19 is an operation diagram in which the movable plate is moved to the front when the carriage approaches the step and the rear drive wheels are positioned so as to be near the center of gravity of the load.

FIG. 20 is an operation diagram at an initial stage showing a state where the dolly is raised to the step portion.

FIG. 21 is an operation diagram in an intermediate stage showing a state where the dolly is raised to the step portion.

FIG. 22 is an operation diagram at the final stage showing a state where the dolly is raised to the step portion.

FIG. 23 is a state diagram showing a state where the dolly is raised to the step portion.

FIG. 24 is a state diagram showing a state in which the dolly has approached a low road surface from a high step portion.

FIG. 25 is an operation diagram in which the movable plate is moved to the rear part when the bogie approaches the step portion that moves to a low road surface, and the front driving wheels are positioned so as to be near the center of gravity of the luggage.

FIG. 26 is an operation diagram at an initial stage showing a state where the carriage is lowered to the step portion.

FIG. 27 is an operation diagram in an intermediate stage showing a state where the carriage is lowered to the step portion.

FIG. 28 is an operation diagram at the final stage showing a state in which the carriage is lowered to the step portion.

FIG. 29 is a state diagram showing a state in which the carriage is lowered from the step portion.

[Explanation of symbols]

 1 Movable plate 2 Cargo carrier 3a Front drive caster 3b Rear drive caster 4a Front drive wheel 4b Rear drive wheel 5a Tip auxiliary wheel caster 5b Rear end auxiliary wheel caster 6a Front auxiliary wheel 6b Rear auxiliary wheel 7a Guide 7b Guide rail 8 Handle 9 Handle 10a Claw 10b Claw 10c Claw 10d Claw 11a Claw wheel 11b Claw wheel 12a Bevel gear 12b Bevel gear 13 Worm shaft 14 Worm gear 15 Pinion gear 16 Rack 17 Changeover switch 18 Changeover switch 20 Belt 21 Car 22 Timing belt Car 23 Timing belt 24 Ball screw 25 Screw shaft 26 Changeover switch 27 Shaft A Mounting shaft B shaft C shaft rod

Claims (1)

[Scope of utility model registration request] 1. A movable plate 1 which is movable with respect to the carrier 2 below a carrier 2 of the carriage, and a pair of rotatable front large-diameter main wheels mounted on the front of the lower surface of the movable plate 1. 4a and a pair of fixed rear large-diameter main driving wheels 4b attached to the rear portion, and a pair of front small-diameter auxiliary wheels 6a and rear small-diameter auxiliary wheels 6b attached to the front and rear ends of the lower surface of the loading platform 2, respectively. And a traverse mechanism that moves and fixes the movable plate 1 in the front-rear direction with respect to the luggage carrier 2, and a handle 8 attached to the luggage carrier 2, which facilitates a step lift.